//登录认证。
async function checkLogin(){
    //把登录状态保存到本次缓冲中，localStorage/cookie;
    if(localStorage.getItem("loginStatus.web.bigdataproject")==null || localStorage.getItem("loginStatus.web.bigdataproject") == undefined){
        await axios.get(baseUrl+"/users/isLogin").then(resp=>{
            if(resp.data.code === 200){
                console.log("发送异步请求成功，判断是否已经登录："+resp.data.data)
                localStorage.setItem("loginStatus.web.bigdataproject",resp.data.data);
            }
        })
    }
    //"true", true
    return JSON.parse(localStorage.getItem("loginStatus.web.bigdataproject"));
}

